We reported about rumors of an Wiimote like motion controller for the Xbox 360 the last couple weeks. Now gaming blog Kotaku opened a whole new direction with identifying Motus and their Darwin 6DOF controller as the possible future Xbox 360 motion controller.

Gyration is actually denying that they work with Microsoft on a motion controller, making the Motus story more plausible at this point.
Kotaku interviews chairman Satayan Mahajan about motion controllers and the plans for their Darwin controller. Darwin is currently in testing at game studios and will work with PC and consoles. Mr. Mahajan is not revealing anything about Microsoft adopting Darwin.
More details on Kotaku.